Summary of Information Regarding Stock Options (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 26, 2015	Dec. 27, 2014
Number of Options
Beginning Balance, number of options	637,221	773,839	1,454,816
Granted, number of options			1,000
Exercised, number of options	(257,460)	(133,518)	(615,077)
Forfeited, number of options	(7,200)	(3,100)	(66,900)
Ending Balance, number of options	372,561	637,221	773,839
Weighted Average Exercise Price per Share
Beginning Balance, Weighted Average Exercise Price per Share	$ 47.24	$ 46.92	$ 44.55
Granted, Weighted Average Exercise Price per Share			58.06
Exercised, Weighted Average Exercise Price per Share	45.63	45.25	41.27
Forfeited, Weighted Average Exercise Price per Share	53.63	52.91	47.51
Ending Balance, Weighted Average Exercise Price per Share	$ 48.24	$ 47.24	$ 46.92
Options exercisable, Number of Options
Options exercisable at the beginning, Number of Options	415,121	379,389	693,516
Options exercisable at the ending, Number of Options	282,461	415,121	379,389
Options exercisable, Weighted Average Exercise Price per Share
Options exercisable at the beginning, Weighted Average Exercise Price per Share	$ 45.12	$ 44.61	$ 42.29
Options exercisable at the ending, Weighted Average Exercise Price per Share	$ 46.39	$ 45.12	$ 44.61